Magnet release for gate doors and for other purposes



B. STEELE Nov. 21, 1944.

Filed July 12, 1940 2 Sheets-Sheet 1 Nov. 21, 1944. B, STEELE 2,363,021

I MAGNET RELEASE FOR GATE DOORS AND FOR OTHER PURPOSES Filed July 12, 1940 2 Sheets-Sheet 2 3 wum flqyanZISCeeZe,

Patented Nov. 21, 1944 MAGNET RELEASE FOR GATE DOORS AND FOR OTHER PURPOSES Bryant Steele, Lexington, Ky., assignor to David E. White, Cleveland, Ohio Application July 12, 1940, Serial No. 345,219

7 Claims.

' in these patents. Magnets constructed in accordance with the teachings of one or more of these patents have been called by the term of Alnico metal magnets or sintered Alnico metal magne These magnets have been of the permanent magnet type, and no means has heretofore been devised to cause the release of the magnetic forces of said magnets.

An object of the present invention is to provide a means for releasing the magnetic forces of, or

demagnetizlng a permanent magnet, such as an "Alnico metal magnet."

Another object of the invention is to provide a race horse starting gate having doors for the release of the horses provided with permanent magnets, such as magnets of Alnico metal with means for affecting the release of, or demagnetization of the magnets.

Other objects will appear hereinafter.

In the drawings:

Figure 1 is a plan view of a pair or doors of a starting gate provided with the device of my invention.

Figure 2 is a side elevation of a permanent magnet provided with the'release device of my invention.

Figure 3 is a top plan view of the device shown in Figure 2, certain parts being shown in section.

Figure 4 is a top plan view of a modification of the device shown in Figures 2 and 3.

Figure 5 is a detail plan view of the magnet block.

Figure 6 is a diagrammatic front elevational view of a horse starting gate, partly broken away.

In the drawings the numeral I indicates a mounting block or base preferably constructed of brass, and provided with side plates 2.

The base is provided with a recess 3 for the reception of the magnet block 4 which is retained in the recess in fixed position by suitable means such as screws which are mounted in the side plates. v

The magnet block may be made in any suitable manner for holding the Alnico or other magnetic material, but I prefer to construct the same as shown in Figure 5, wherein 6 is a brass or bronze alloy center portion partially surrounded by a steel or other ferrous metal portion 1 of general horse shoe configuration. The numeral 9 indicates spaces for the reception of brass strips 10 which do not extend all the way to the end of the magnet block at one of their ends, and which connect with or abut the brass center portion at their other ends.

Set into the steel or other ferrous metal portion is the sintered Alnico magnetic plug 8, an alloy composed of aluminum, nickel, iron and cobalt. in accordance with the above enumerated patents.

The side plates 2 mount bearing portions 12 each of which is provided with an elongated slot I3 in which seat the bearings or pins 14 that extend from each side of the secondary shortcircuiting armature or release plate 15. This plate is therefore pivotally mounted in the slots I3. The plate is provided adjacent its other end with an upstanding ear l5 having an aperture l1 for the reception of the nose I9 of the latch arm I 8 as shown in Figures 2 and 3.

An electro-magnet is indicated at 20 and is provided with a core 2| which when energized pulls the latch arm downwardly (Figure 2), to release the nose from the aperture I1 to thereby permit the spring 22 to force the secondary armature into contact with one side of the magnet block. The spring 22 is mounted on top of the base I.

The primary armature is designated by the numeral 23. This preferably consists of a central bronze portion 24 having fixedly attached thereto a ferrous metal portion 25 and on the opposite side another ferrous metal portion 26. The ferrous metal portion 25 consists of a series of blocks providing slots 21. Strips of bronze material 28 extend almost to the edge of the slots and connect or abut at their opposite ends with the central bronze portion 24.

The primary armature may be guided in its movements toward the magnet block 4 by a metal strap 29 secured to the side plates 2 by screws 30.

The electro-magnet shown may be of any well known construction and may also be mounted as shown in the alternate construction shown in Figure 4 wherein one of the side plates is indicated at 3|. These plates are similar to the plates 2 and are provided with ears 32 having elongated slots 33 in which are mounted the pins 34 forming the pivots for the secondary armature or release plate 35. The electro-ma net is indicated by the numeral 36 and is mounted on the arm 31, which latter is affixed by suitable titions 62 and S3.

means such as a screw 38 to the base 39. The secondary plate is urged to its closed position by the spring 40 which is mounted on the base by means of the screw 4|. The electro-magnet is provided with a core 42.

The primary armature is indicated by the numeral 43. This armature is the same or similar to that disclosed in Figures 2 and 3 and may be guided towards the magnet block, which is not illustrated but which is the same as that shown in Figure 3, by the strap 44 which is aflixed to the base by screws 45.

I have shown in Figure 1 one use to which my invention may be applied. The numerals 45 and 41 indicate pivoted doors of the type illustrated at H in my patent, No. 2,193,257, granted March 12, 1940. As illustrated the primary armature 23 is mounted on a supporting strap 48 connected adjacent to the end of the door 46. The magnet and release shown in Figures 2 and 3 are mounted adjacent to the juxtapositioned end of the other door 41. The electro-magnet 20 is mounted on an arm 49 which is also amxed to the door 41. The electromagnet indicated in Figures 2 and 3, or Figure 4 is connected into the circuit 50 (Fi ure 1). This circuit has a source and an electrical switch 52.

The primary armature 23 will be released from the magnet block 4 as follows: actuation of the switch 52 energizes the electro-magnet which attracts the armature pulling latch arm l8 downwardly as shown in Figure 2, thus moving the nose IQ of said arm 18 out of the aperture H. The release plate i5 is now free under the action of spring 22 to move to its closed position against the Alnico magnet block 4. The magnetic flux which has passed through the primary armature from the magnet will now be diverted or shunted and will now pass through the plate Hi. In other words the flux path will pass through the plate l5 instead of passing through the primary armature 23. When this occurs the springs tending to open the doors 46 and 41 (shown in Figure 3 my prior patent above) will immediately cause the opening of said pair of doors in the same manner as described in my patent. It is to be understood that there are as many pairs of doors for magnets as shown in Figure 1 as there are pairs of stall partitions. It is of course obvious also that each magnet may be controlled from a single circuit as indicated in Figure 5 of my patent.

Figure 6 shows another manner of applying my invention to a starting gate for race tracks. In the figures 54 and 55 indicate vertical posts pivotally mounted to the superstructure 53 and par- Rigidly mounted on these posts so as to swing therewith are the doors 56 and 51.

The arms 58 and 59 are rigidly mounted on the posts 54 and 55 respectively and swing therewith. When the doors are in closed position as indicated in the figure the magnet 6|! mounted on the arm 58 and the primary armature 6| mounted on the arm 59 contact each other and hold the pair of doors 56 and 51 in closed position until the electro-magnet is operated to release the armature 6| from the magnet 60. The doors are opened by springs not shown but as indicated in Figure 3, my former patent above referred to. The magnet, and electro-magnet diagrammatically illustrated in Figure 6 are the same in detail as that disclosed in Figures 2, 3 or 4 of this application.

It will b noted that in the structure shown by Figures 2 and 3 the secondary armature is held in its open position by the latch l8 until the current is turned on. When the current is turned on the latch arm I8 is drawn downwardly to release the said secondary armature. In Figure 4 however no latch is provided, and the secondar armature 35 is retained in its open position as long as the current is on so that the core 42 is energized by current in the magnet 36.

It is to be understood that the term electromagnet means" in the claims refers to the parts l8, l9 and 20 shown in Figures 2 and 3, or the parts 36 and 42 in Figure 4.

It is to be understood that the device of the present invention may be used not only on gates for starting horses at a race track, but that the magnet release of this invention may be used for any purpose to which it is applicable. Other uses to which my invention may be put include this application for use with a magnetic chuck, or in fact any use which includes a permanent magnet or an electro-magnet.

I claim:

1. In combination, a permanent magnet, a primary armature therefor normally held by the flux of the permanent magnet in substantial contact therewith, shunting means for shunting magnetic flux away from said primary armature including a secondary armature adapted for movement toward and away from said magnet, spring means for urging said secondary armature towards said magnet, latch means for retaining said secondary armature out of contact with said magnet to prevent movement of said armature by said spring means, and electro-magnetic means for operating said latch means to thereby release said secondary armature when said electro-magnetic means is energized.

2. In combination, a permanent magnet, a primary armature therefor normally held by the fiux of the permanent magnet in substantial contact therewith, shunting means for shunting magnetic flux away from said primary armature including a secondary armature pivotally mounted on said permanent magnet adapted for movement toward and away from said magnet, spring means for urging said secondary armature toward said magnet, latch means for retaining said secondary armature out of contact with said magnet to prevent movement of said armature by said spring means, and electro-magnetic means for operating said latch means to thereby release said secondary armature when said electro-magnetic means is energized.

3. In combination, a permanent magnet, a primary armature therefor normally held by the flux of the permanent magnet in substantial contact therewith, shunting means for shunting magnetic flux away from said primary armature including a secondary armature adapted for movement toward and away from said magnet, biasing means for urging said secondary armature towards said magnet, and electro-magnetic means for retaining said secondary armature in a position away from said magnet when said electro-magnetic means is energized.

4. In combination, a permanent magnet, a primary armature therefor normally held by the flux of the permanent magnet in substantial contact therewith, shunting means for shunting magnetic flux away from said primary armature including a secondary armature pivotally mounted on said permanent magnet adapted for movement toward and away from said magnet, biasing means for urging said secondary armature into contact with said magnet, and electro-magnetic means for retaining said secondary armature in a position away from said magnet when said electro-magnetic means is energized.

5. In combination, a permanent magnet, including a part composed of an alloy of aluminum, nickel, iron and cobalt, a primary armature therefor normally held by the flux of the permanent magnet in substantial contact therewith, a secondary armature mounted on said magnet for movement int contact with or away from said magnet, means normally urging said secondary armature into contact with said magnet, and electro-magnetic means located adjacent to said secondary armature for holding said secondary armature away from said magnet when the electro-magnetic means is energized.

6. In combination, a releasable permanent magnet, a primary armature for said magnet responsive to the flux thereof and adapted to move toward and away from said magnet in a longitudinal direction thereof, a secondary armature mounted on said magnet and adapted to move in a transverse direction to that of said primary armature, means biasing said secondary armature into contact with said magnet, and electro-magnetic means for retaining said secondary armature in a position out of contact with said magnet.

7. In a device of the character described, a permanent magnet, a primary armature therefor normally held by the flux of the permanent magnet in substantial contact therewith, means biasing the primary armature to move away from the permanent magnet upon reduction of said flux through the primary armature, a secondary armature mounted for movement toward the permanent magnet to shunt the flux thereof through the secondary armature and thereby reduce the flux through the primary armature and for movement away from the permanent magnet, means biasing the secondary armature to move toward the permanent magnet, and electro-magnetic means for controlling the movement of the secondary armature.

BRYANT STEELE. 

